Apparatus for cooling NMR coils

An NMR probe comprising:

• a) a vacuum insulated container having an outer wall and an inner wall concentric to the outer wall, the inner wall defining a space for insertion of a sample and the outer walls and the inner walls defining a vacuum space:
• b) a receiver coil assembly positioned within the vacuum space comprising a receiver coil on a thermally conductive substrate, a heat sink attached to the substrate and a heat exchanger attached to the heat sink, whereby the receiver coil is in close proximity to the inner wall, and the substrate provides a separation between the receiver coil and the heat sink;
• c) a refrigeration means for cooling a fluid to a cryogenic temperature;
• d) a tube connected to the heat exchanger for carrying the cooled fluid to the heat exchanger.

A system for cooling a device to cryogenic temperatures comprising:

• a) a cooler for cooling a fluid to a desired temperature;
• b) a receptacle for a coldfinger assembly comprising:
• 1) a hollow cylinder, the cylinder being open at one end and having a thermally conductive cap attached to the opposite end, the hollow cylinder having an inside diameter larger than the outside diameter of the rigid tube,
• 2) a thermally conductive substrate having a surface having a proximal region and a distal region, the proximal region being attached to the thermally conductive block;
• 3) a receiver coil deposited on the distal region of the substrate;
• c) a coldfinger slideably positioned within the receptacle comprising:
• 1) a rigid tube having two ends, the rigid tube having an outside diameter;
• 2) a thermoconductive tip connected to one end of the rigid tube;
• 3) a flexible tube connected to the other end of the rigid tube, whereby the tip, rigid tube and flexible tube define a vacuum space;
• 4) a first transfer line connecting the cooler to the tip for carrying a cold fluid from the cooler to the tip, the second transfer line being positioned within the vacuum space;
• 5) a second transfer line connecting the cooler to the tip for carrying a cold fluid from the tip to the cooler, the second transfer line being positioned within the vacuum space;
• wherein, the coldfinger assembly provides cooling of the receiver coil to a desired temperature.